AUTHORS: Ruby Valadez, University of Wisconsin-Stevens Point; Josiah Gritter, University of Wisconsin-Stevens Point; Elizabeth Peters, University of Wisconsin-Stevens Point
ABSTRACT: The Northern Saw-whet Owl (Aegolius acadicus) (NSWO) is a mesopredator commonly found within upland ecosystems across North America. NSWO’s migrate in the fall from September to December, peaking around mid-October, making them relatively abundant in central Wisconsin during this time. Our project began in 2007 and continues to operate at Sandhill Wildlife Area in Babcock, WI, and we have captured over 1,300 NSWOs. These owls are captured using call-playback devices and mist nets. The birds are banded using USGS aluminum leg bands, contributing to national banding data on Northern Saw-whet Owls. Wing and tail chords, weight, age, and sex of birds are recorded with each capture. Our project has previously focused on studying migration patterns and we are curious how migration timing has changed over time. We will use our historic banding data to analyze the timing of migration from year to year and determine if migration is occurring earlier or later. We will also investigate if there has been a shift in the pattern of irruption, which typically occurs every four years.
